Publications (92) View all
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Article: Dialysate Calcium Concentration and Mineral Metabolism in Long and Long-Frequent Hemodialysis: A Systematic Review and Meta-analysis for a Canadian Society of Nephrology Clinical Practice Guideline.
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ABSTRACT: BACKGROUND: Patients treated with conventional hemodialysis (HD) develop disorders of mineral metabolism that are associated with increased morbidity and mortality. More frequent and longer HD has been associated with improvement in hyperphosphatemia that may improve outcomes. STUDY DESIGN: Systematic review and meta-analysis to inform the clinical practice guideline on intensive dialysis for the Canadian Society of Nephrology. SETTING & POPULATION: Adult patients receiving outpatient long (≥5.5 hours/session; 3-4 times per week) or long-frequent (≥5.5 hours/session, ≥5 sessions per week) HD. SELECTION CRITERIA FOR STUDIES: We included clinical trials, cohort studies, case series, case reports, and systematic reviews. INTERVENTIONS: Dialysate calcium concentration ≥1.5 mmol/L and/or phosphate additive. OUTCOMES: Fragility fracture, peripheral arterial and coronary artery disease, calcific uremic arteriolopathy, mortality, intradialytic hypotension, parathyroidectomy, extraosseous calcification, markers of mineral metabolism, diet liberalization, phosphate-binder use, and muscle mass. RESULTS: 21 studies were identified: 2 randomized controlled trials, 2 reanalyses of data from the randomized controlled trials, and 17 observational studies. Dialysate calcium concentration ≥1.5 mmol/L for patients treated with long and long-frequent HD prevents an increase in parathyroid hormone levels and a decline in bone mineral density without causing harm. Both long and long-frequent HD were associated with a reduction in serum phosphate level of 0.42-0.45 mmol/L and a reduction in phosphate-binder use. There was no direct evidence to support the use of a dialysate phosphate additive. LIMITATIONS: Almost all the available information is related to changes in laboratory values and surrogate outcomes. CONCLUSIONS: Dialysate calcium concentration ≥1.5 mmol/L for most patients treated with long and long-frequent dialysis prevents an increase in parathyroid hormone levels and decline in bone mineral density without increased risk of calcification. It seems prudent to add phosphate to the dialysate for patients with a low predialysis phosphate level or very low postdialysis phosphate level until more evidence becomes available.American Journal of Kidney Diseases 04/2013; · 5.43 Impact Factor -
Article: Canadian Society of Nephrology Guidelines for the Management of Patients With ESRD Treated With Intensive Hemodialysis.
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ABSTRACT: Intensive (longer and more frequent) hemodialysis has emerged as an alternative to conventional hemodialysis for the treatment of patients with end-stage renal disease. However, given the differences in dialysis delivery and models of care associated with intensive dialysis, alternative approaches to patient management may be required. The purpose of this work was to develop a clinical practice guideline for the Canadian Society of Nephrology. We applied the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach for guideline development and performed targeted systematic reviews and meta-analysis (when appropriate) to address prioritized clinical management questions. We included studies addressing the treatment of patients with end-stage renal disease with short daily (≥5 days per week, <3 hours per session), long (3-4 days per week, ≥5.5 hours per session), or long-frequent (≥5 days per week, ≥5.5 hours per session) hemodialysis. We included clinical trials and observational studies with or without a control arm (1990 and later). Based on a prioritization exercise, 6 interventions of interest included optimal vascular access type, buttonhole cannulation, antimicrobial prophylaxis for buttonhole cannulation, closed connector devices, and dialysate calcium and dialysate phosphate additives for patients receiving intensive hemodialysis. We developed 6 recommendations addressing the interventions of interest. Overall quality of the evidence was very low and all recommendations were conditional. We provide detailed commentaries to guide in shared decision making. The main limitation was the very low overall quality of evidence that precluded strong recommendations. Most included studies were small single-arm observational studies. Three randomized controlled trials were applicable, but provided only indirect evidence. Published information for patient values and preference was lacking. In conclusion, we provide 6 recommendations for the practice of intensive hemodialysis. However, due to very low-quality evidence, all recommendations were conditional. We therefore also highlight priorities for future research.American Journal of Kidney Diseases 04/2013; · 5.43 Impact Factor -
Article: Pre to post-dialysis plasma sodium change better predicts clinical outcomes than dialysate to plasma sodium gradient in quotidian hemodialysis.
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ABSTRACT: Sodium balance across a hemodialysis treatment influences interdialytic weight gain (IDWG), pre-dialysis blood pressure, and the occurrence of intradialytic hypotension, which associate with patient morbidity and mortality. In thrice weekly conventional hemodialysis patients, the dialysate sodium minus pre-dialysis plasma sodium concentration (δDPNa+) and the post-dialysis minus pre-dialysis plasma sodium (δPNa+) are surrogates of sodium balance, and are associated with both cardiovascular and all-cause mortality. However, whether δDPNa+ or δPNa+ better predicts clinical outcomes in quotidian dialysis is unknown. We performed a retrospective analysis of clinical and demographic data from the Southwestern Ontario Regional Home Hemodialysis program, of all patients since 1985. In frequent nocturnal hemodialysis, δPNa+ was superior to δDPNa+ in predicting IDWG (R(2) = 0.223 vs. 0.020, P = 0.002 vs. 0.76), intradialytic change in systolic (R(2) = 0.100 vs. 0.002, P = 0.02 vs. 0.16) and diastolic (R(2) = 0.066 vs. 0.019, P = 0.02 vs. 0.06) blood pressure, and ultrafiltration rate (R(2) = 0.296 vs. 0.036, P = 0.001 vs. 0.52). In short hours daily hemodialysis, δDPNa+ was better than δPNa+ in predicting intradialytic change in diastolic blood pressure (R(2) = 0.101 vs. 0.003, P = 0.02 vs. 0.13). However, δPNa+ was better than δDPNa+ in predicting IDWG (R(2) = 0.105 vs. 0.019, P = 0.04 vs. 0.68) and pre-dialysis systolic blood pressure (R(2) = 0.103 vs. 0.007, P = 0.02 vs. 0.82). We also found that the intradialytic blood pressure fall was greater in frequent nocturnal hemodialysis patients than in short hours daily patients, when exposed to a dialysate to plasma sodium gradient. These results provide a basis for design of prospective trials in quotidian dialysis modalities, to determine the effect of sodium balance on cardiovascular outcome.Hemodialysis International 04/2013; · 1.54 Impact Factor -
Article: Novel techniques and innovation in blood purification: a clinical update from Kidney Disease: Improving Global Outcomes.
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ABSTRACT: Mortality in patients with end-stage renal disease (ESRD) remains unacceptably high. Emerging techniques and advances in dialysis technology have the potential to improve clinical outcomes in the ESRD population. This report summarizes the deliberations and recommendations of a conference sponsored by Kidney Disease: Improving Global Outcomes to address the following questions: (1) what is the appropriate frequency and duration of hemodialysis; (2) how should we optimize water quality and dialysate composition; and (3) what technical innovations in blood purification and bioengineering can result in better clinical outcomes? The conference report will augment our current understanding of clinical practice in blood purification and will pose several high-priority research questions.Kidney International advance online publication, 16 January 2013; doi:10.1038/ki.2012.450.Kidney International 01/2013; · 6.61 Impact Factor -
Article: Relationship of pharyngeal water content and jugular volume with severity of obstructive sleep apnea in renal failure.
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ABSTRACT: Background In patients with end-stage renal disease (ESRD), fluid overload may contribute to their high prevalence of obstructive sleep apnea (OSA) by increasing the amount of fluid displaced from the legs into the neck overnight, and possibly compressing the upper airway (UA). Indeed, in ESRD patients, the amount of overnight rostral fluid displacement from the legs is related to the frequency of apneas and hypopneas per hour of sleep (apnea-hypopnea index, AHI). We, therefore, hypothesized that in ESRD patients, the greater the UA-mucosal water content (UA-MWC) and internal jugular vein volume (IJVVol), the higher the AHI.Methods We studied 20 patients with ESRD on thrice weekly hemodialysis who had undergone diagnostic polysomnography (age 41.0 ± 12.3 years, with a body mass index (BMI) of 25.8 ± 6.3 kg/m(2) and an AHI of 20.2 ± 26.8). The leg fluid volume (LFV) was measured by bioelectric impedance. The IJVVol and MWC were measured by UA magnetic resonance imaging (MRI).ResultsThe only significant independent correlates of the AHI were IJVVol (r = 0.801, P < 0.0001) and UA-MWC (r = 0.720, P = 0.0005) which together explained 72% of its variability.Conclusions These data suggest that fluid overload via increased IJVVol, and UA-MWC, contributes to the pathogenesis of OSA in patients with ESRD. These findings help us to explain the high prevalence of OSA in ESRD patients, and attenuation of OSA in association with nocturnal dialysis. They also suggest the need for randomized trials to determine whether more aggressive fluid removal in ESRD patients will alleviate OSA.Nephrology Dialysis Transplantation 11/2012; · 3.40 Impact Factor
